Justification:
Listed as Critically Endangered based on an estimated area of occupancy of less than 10 km² and an extent of occurrence probably not much greater, it occurs as a severely fragmented population and there is a continuing decline in its forest habitat due to slash-and-burn agriculture and logging.

This chameleon is endemic to the island of Madagascar where it has been confirmed from two localities in the east, both in the Anosibe An'ala District in the Alaoatra Mangoro Region. The type locality is a small and degraded forest fragment of about 1.5 km in length and less than 0.3 km in width, just less than one kilometre north of Tarzanville, and the second is Ambatofotsy (19°32'35.2 S, 48°18'59.5 E, 907 m a.s.l.), a forest fragment (of ca. 6 km in length and 1.5 km in width). Recorded elevation range is 800-910m. Several areas around the known distribution range of C. tarzan have been surveyed but did not reveal additional localities for the new species. The forest remnants between the Manambolo and Mangoro river valleys are mostly above 900 m altitude and therefore are probably not populated by the new species. The same is true for the forests west of the Mangoro River, including an area east of Tsinjoarivo surveyed in 2010, in which C. tarzan was not recorded. Surveys in forest fragments of littoral forests in an area between Vatomandry, Mahanoro, and the estuary of the Mangoro River did not yield any C. tarzan. The species may occur in other forest fragments to the east and south of the Anosibe An'ala District in forests lower than 910 elevation (Gehring et al. 2010). Even if it occurred throughout the area between known sites it would have a distributional extent of only around 91 km², but based on current knowledge and survey work the actual range is much smaller (perhaps as small as 9-10 km², the approximate combined area of known localities) and this lizard has a very limited area of occupancy.

This species was locally abundant during April (Gehring et al. 2010). Do to ongoing land clearance at and between the known sites, it is presumed that the population is both declining and severely fragmented.

This species has only been recorded from lowland moist forest. This species roosts in forest vegetation at night, 1-4 m above ground (Gehring et al. 2010). In April the population consisted mostly of hatched juveniles and one female was gravid (Gehring et al. 2010).

There is ongoing clearance of humid forest at both of the sites from where C. tarzan was collected in 2009. The main threat is from slash and burn farming at the forest edges, but selective logging also occurs in some areas of the forests. There is some evidence of a recent increase in illegal artisanal gold mining in the area.

This species has not been found inside Madagascar's existing protected area network. One of the forests from where it was collected, at Ambatofotsy, is currently being established as a new protected area. Additional efforts are needed at this site, and near Tarzanville, to conserve the remaining forest. There is the possibility that the species may be shown to occur more widely to the east and south of the Anosibe An'ala District in forests lower than 910 elevation, and these are a priority for further survey work; additional surveys are also needed in the forests around Tarzanville to establish whether this species occurs there.